New Correlation for Predicting Undersaturated Oil Compressibility for Mishrif Reservoir in the Southern Iraqi Oil Fields

Reservoir fluids properties are very important in reservoir engineering computations such as material balance calculations, well testing analyses, reserve estimates, and numerical simulations. Isothermal oil compressibility is required fluid flow problems, extension of from values at the bubble point pressure to higher pressures interest calculations (Ramey, Spivey, McCain). a measure fractional change volume changed constant temperature (McCain). The most accurate method for determining laboratory PVT analysis; however, evaluation exploratory wells often require an estimate behavior prior obtaining representative sample. Also, experimental data unavailable.Empirical correlations used these purposes.This paper developed new mathematical model calculating undersaturated using 129 experimentally obtained points analyses 52 bottom hole samples Mishrif reservoirs southern Iraqi fields. correlation Statistical Analysis System (SAS) by applying nonlinear multiple regression method. It was found that estimates crudes fields much better than published ones. average absolute relative error 7.16%.